Kevin Mazur/WireImage(LONDON) -- Lindsay Lohan may be in court-ordered rehab at the moment, but she insists she's not a heavy drug user or drinker.

In an interview with CNN host Piers Morgan for Britain's Daily Mail conducted a few weeks ago, Lohan says she's only used cocaine "maybe four or five times" in her life. She pleaded guilty in 2007 to being under the influence of cocaine in connection with a DUI case.

The Mean Girls star, who checked into the Betty Ford Center on Thursday night for a mandatory 90-day stint in connection with her car crash case, admits that she's tried marijuana and ecstasy, the latter of which she says she liked "better than the others."

As for her alcohol consumption, the 26-year-old insists, "I’ve never been a huge drinker. I’ve never woken up in the morning and had a drink."

So why does Lohan need to be in rehab? Morgan asks her that very question.

Her response: "I don’t think there’s anything wrong with people taking time to just be by themselves. I think people want to see me do that. They will keep saying the same things about me if I don’t. I don’t think it will be a bad thing for me to be away with myself for three months."

Lohan notes that she's been ordered to rehab by a court six times, adding, "I could write the book on rehab. Constantly sending me to rehab is pointless. The first few times I was court-ordered to rehab it was like a joke, like killing time." However, she stresses that her latest rehab stay will be a good thing for her.

In the interview, Lohan also reflects on her relationship with her father, Michael Lohan, saying, "He definitely needs to see a therapist."

She claims that she once caught him cheating on her mother, DinaLohan, while her parents were married.

Morgan asks Lindsay about her sexual orientation. She answers that she is straight, though at one point she was in love with her former girlfriend, Samantha Ronson.

Lindsay comments, "I have made out with girls before, and I had a relationship with a girl. But I think I needed to experience that and I think I was looking for something different."

Lindsay says she is not dating anyone at the moment.

When asked if any celebrities have been helpful to her, Lindsay replies, "MerylStreep was nice. She just advised me on my acting and what I needed to do differently." Lindsay and Streep both starred in the 2006 movie A Prairie Home Companion.